Rinse-off skin care compositions containing cellulosic materials

ABSTRACT

The compositions and methods of this invention relate to a rinse-off skin care composition containing hydrophobic, linear cellulose particles having an average length of from about 1 to about 1000 μm, a particle aspect ratio from about 1000 to about 2 and a thickness of from about 1 to about 500 μm; at least one cleansing agent selected from the group consisting of a saponified fat and a surfactant; and a cosmetically acceptable carrier.

This application is a continuation of U.S. application Ser. No. 13/799,365 filed Mar. 13, 2013, which is a continuation-in-part of U.S. application Ser. No. 13/673,477 filed Nov. 9, 2012, the complete disclosures of which are hereby incorporated herein by reference for all purposes.

FIELD OF THE INVENTION

The compositions of this invention relate to rinse-off skin care compositions containing hydrophobic, linear cellulosic particles that reduce the presence of oil-related substances on skin.

BACKGROUND OF THE INVENTION

Oily skin is shiny, thick and dull colored. Often, chronically oily skin has coarse pores and pimples and other embarrassing blemishes. Furthermore, chronically oily skin can be prone to developing blackheads. In this type of skin, the oil-producing sebaceous glands are overactive and produce more oil than is needed. The oil flows out of the follicles and gives the skin an undesirable greasy shine. The pores are enlarged and the skin has a coarse look. While oily skin is common in teenagers, it can occur at any age.

Generally, individuals having oily skin attempt to treat areas of oiliness in order to prevent outbreaks of acne and to diminish shininess. The conventional treatments available include soaps or surfactant based cleansers, astringents with alcohol and clay or mud masks. Oil absorbing materials such as clay or salt have also been used to attempt to treat this condition.

Individuals having oily or shiny skin conditions prefer a treatment that can remove the shine without drying the skin. However, there is a lack of effective skin care products on the market today that address this consumer need. Oil absorbing powders such as silica, aluminum starch, and talc have been used in the cleansing products to help dry the skin surface oil, but they also tend to dry the skin and oily and shiny skin tend to come back quickly, usually in two to three hours.

Such benefits as reducing the appearance of oil on skin are particularly difficult to deliver out of a rinse-off composition such as a cleanser. This is due to the relatively short contact time between the application of a cleansing composition to the skin and the activity of rinsing the cleansing composition off the skin.

Thus, it would be desirable to have compositions and methods of treatment that address the condition of oily skin while keeping skin hydrated.

SUMMARY OF THE INVENTION

The compositions and methods of this invention relate to a rinse-off skin care composition comprising hydrophobic, linear cellulose particles having an average length of from about 1 to about 1000 μm, a particle aspect ratio from about 1000 to about 2 and a thickness of from about 1 to about 500 μm; at least one cleansing agent selected from the group consisting of saponified fat and surfactants; and a cosmetically acceptable carrier.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of Infrared spectra of various cotton particles and cellulose.

FIG. 2 is a graph of Infrared spectra of various solvent extracts from hydrophobic cotton particles and dimethicone.

FIG. 3 is a graph illustrating oil absorption rates of hydrophilic and hydrophobic cotton particles.

FIG. 4 is a graph of the speed of water absorption measured from various hydrophobic and hydrophilic cotton particles.

FIG. 5 is a graph illustrating average oil absorption capacity of various hydrophobic and hydrophilic cotton particles.

FIG. 6 is a graph illustrating average water absorption capacity of various hydrophobic and hydrophilic cotton particles.

FIG. 7 is a graph illustrating average sebum measurements of various cleanser formulations over time.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “hydrophobic” means materials having a surface contact angle with squalene of less than 40 degrees and/or a surface contact angle with water of greater than 90 degrees. The term “surface contact angle” means the internal angle between a surface and a liquid droplet resting on that surface. Surface tension (liquid) or surface free energy (solid) is considered to be a resulting balance between the molecular interactions of the liquid-liquid and air-liquid or solid-solid and air-solid phase at the interfacial layer. The term “contact angle” is a convenient and useful parameter to determine the surface free energy and wettability of any given solid surface due to the non-deformability of the solid. The contact angle is determined by measuring the angle formed between substrate surface where a liquid droplet is placed and the tangent to the drop surface from the contact point. High contact angles correspond to poor wetting of the surface by the liquid and low contact angles signify good wetting. If a liquid spreads on the surface, the contact angle is considered to be zero and complete wetting is said to occur.

Contact angle measurements can be employed to determine the wettability of human skin by a variety of liquids, including hydrophobic liquids such as squalene and hydrophilic liquids, including water. A smaller contact angle with a non-polar liquid (such as squalene) corresponds to a more hydrophobic material while a smaller water contact angle corresponds to a more hydrophilic material.

In accordance with the methods and compositions of this invention, the water contact angle of the hydrophobic, linear cellulose particles is preferably greater than 90 degrees, preferably greater than 100 degrees and more preferably greater than 120 degrees.

As used herein, the term “oil absorption capacity and retention” refers to the weight percentage of the oil absorbed by the hydrophobic, linear cellulose particles useful in the compositions and methods of this invention. High oil absorption capacity and retention corresponds to an increased hydrophobic property. The oil absorption capacity and retention of the hydrophobic, linear cellulose particles of the compositions of this invention is preferably from about 150 to about 500, and more preferably from about 300 to about 500 (% weight oil/weight particles).

As used herein, the term “particle” means a small localized object to which can be ascribed physical properties such as volume or mass. As used herein, the term “powder” is used synonymously to “particle”, as defined herein.

As used herein, the term “linear particle” means a particle having one dimension (“length”) that is greater than another dimension (“width”). Linear particles may be measured and defined by size by subjecting such particles to analysis with respect to a series of sieves having different mesh sizes. Generally, a sample of linear particles may have a distribution of particle sizes throughout the sample. Thus, linear particle sizes as expressed herein are expressed as an average particle size and reflect the average length of the particles contained within the sample.

Preferably, the size of linear particles useful in the compositions and methods of this invention is less than about 1000 μm in length, more preferably, it ranges from about 1 to about 1000 μm, and most preferably from about 10 to about 500 μm. The preferred width of linear particles useful in the compositions and methods of this invention are about 5 to about 25 μm. More preferably, they are from about 5 to about 20 μm in width.

As used herein, the term “particle aspect ratio” means the ratio of the length of a particle to its width. Preferably, the particle aspect ratio of the particles useful in the compositions and methods of this invention is from about 2 to about 1000. More preferably, the particle aspect ratio is from about 2 to about 500 and most preferably, from about 5 to about 200.

As used herein, the term “cellulose” refers to a polysaccharide material consisting of long unbranched chains of linked glucose units, having the chemical structure set forth in Formula I below:

Cellulose, the most abundant biomass on the surface of the earth, has provided mankind with functional, low cost and renewable raw material.

Cellulose materials useful in the compositions and methods of this invention may be derived from cotton, corn, wood pulp and bamboo pulp, silk, cork and the like. Preferably, the cellulose materials useful in the compositions of this invention are derived from cotton. More preferably, the cellulosic particles are from fibers recovered from post-industrial scrap. Such scrap is derived from waste or other pre-consumer cotton products from, for example, the apparel, carpet, furniture and household goods industries. Synthetic or regenerated cotton or cellulose materials may also be used as sources for the cellulose particles useful in the compositions and methods of this invention, including rayon, viscose, cellophane, and other cellulosic materials with a uniform and reproducible molecular size and distribution.

The cellulose materials useful in the compositions and methods of this invention may be derived directly from the source plant (referred to herein as, “raw” particles) or may be generated from cloth or nonwoven materials previously formed from plant or cellulose fibers (referred to herein as “regenerated” particles). For example, cotton cloth may be processed so as to break the cloth into small particles and/or uniform fiber length by cutting the length of the cotton fibers from inches to microns. This random-cut fiber is available in several grades, white, dark, and unbleached, with average fiber lengths from about 1 micron to about 1000 microns and preferably from about 2 microns to about 500 microns.

It is believed that hydrophilic, raw cellulose particles having similar size, aspect ratio and other characteristics to those of hydrophobic linear particles useful in the present invention may also be useful in the rinse-off and cleansing compositions of this invention.

Typical mechanical milling processes such as those useful in cutting down the size of the cellulose materials useful in the compositions and methods of this invention, for example, are described in U.S. Pat. No. 7,594,619 and U.S. Pat. No. 6,656,487, which are hereby incorporated herein by reference.

Generally, the hydrophobic cellulose particles useful in the compositions of this invention may be processed according to the following methods.

One such method comprises mixing a cellulosic material derived from post-industrial scrap, as defined above, with at least one of grinding aids selected from the group including water, fatty acids, synthetic polymers and organic solvents, and, after mixing, mechanically grinding the mixture.

Another method of obtaining hydrophobic cellulose particles is freezing a cellulosic material derived from post-industrial scrap at a low temperature, and then mechanically grinding said frozen material.

The cellulose particles useful in the compositions and methods of this invention may be further treated with hydrophobic agents to yield hydrophobic cellulose particles. For example, a hydrophobic coating agent may be used to treat the cellulose particles. The hydrophobic coating agent may be any such agent known to one of skill in the art. Preferred hydrophobic coating agents react chemically with the cellulose particle to provide a durable covalent bond thereto and have hydrophobic chemical backbones or substituents that can provide a hydrophobic outer layer around each individual cellulosic particle. The coating agent may react, for example, with hydroxyl groups, available oxygen atoms present on the surface of the cellulose particle being coated.

Hydrophobic agents may include, but are not limited to, low water soluble organic compounds such as metal soap, e.g., a metal myristate, metal stearate, a metal palmitate, a metal laurate or other fatty acid derivatives known to one of skill in the art. Other hydrophobic agents may include an organic wax, such as a synthetic wax like polyethylene or a natural wax like carnauba wax. Hydrophobic agents useful in coating the cellulose particles useful in the compositions and methods of this invention may also be long chain fatty acids or esters such as stearic acid, oleic acid, castor oil, isododecane, silicone, and their derivatives, non-water soluble polymers, e.g. high molecular weight methylcellulose and ethylcellulose, and high molecular water insoluble fluoropolymers etc., polymerized siloxanes or polysiloxanes with the chemical formula [R₂SiO]n, where R is an organic group such as methyl, ethyl, or phenyl, such as dimethicone, dimethicone copolyol, dimethicone ester; methicone and their derivatives. Examples of hydrophobic linear cotton particles useful in the present invention include, but are not limited to, Cotton Fiber Flock CD60, available from Goonvean Fiber and W200 White Cotton Flock, available from International Fiber Corporation.

The hydrophobic cellulose particles of this invention may be formulated into a variety of “rinse-off” skin care applications.

The term “rinse-off” as used herein indicates that the compositions of the present invention are used in a context whereby the composition is ultimately rinsed or washed from the treated surface, (e.g. skin or hard surfaces) either after or during the application of the product. These rinse-off compositions are to be distinguished from compositions which are applied to the skin and allowed to remain on the skin subsequent to application.

The rinse-off, cellulose particle-containing compositions of this invention may be formulated into a wide variety of rinse-off compositions for personal care, including but not limited to liquid cleansers, creamy cleansers, gel cleansers, soaps and makeup removers.

The topical cosmetic compositions of this invention may contain a carrier, which should be a cosmetically and/or pharmaceutically acceptable carrier. The carrier should be suitable for topical application to the skin, should have good aesthetic properties and should be compatible with other components in the composition.

These product types may comprise several types of cosmetically acceptable topical carriers including, but not limited to solutions, emulsions (e.g., microemulsions and nanoemulsions), gels, solids and liposomes. The following are non-limitative examples of such carriers. Other carriers can be formulated by those of ordinary skill in the art.

The rinse-off compositions of this invention preferably contain at least one cleansing agent selected from the group consisting of fatty acid soaps and synthetic surfactants and/or a mixture of such materials. Optionally, the compositions of this invention contain one or more skin conditioning agents. The compositions of this invention may also contain one or more skin therapeutic agents. Preferably, the pH of the compositions of this invention ranges from about 2 to about 11. More preferably, the pH ranges from about 3 to about 10.

The compositions of this invention may contain a saponified fat, for example, fatty acid soaps containing from about 6 to about 22 carbon atoms, preferably form about 8 to about 18 carbon atoms, and more preferably from about 12 to about 18 carbon atoms. Fatty acid soaps having from about 8 to about 18 carbon atoms are preferably present in the compositions of this invention in an amount of from about 1 to about 60% by weight.

Preferably, the fatty acid soaps useful in the compositions of this invention are organic soaps obtained using organic neutralizers including, but not limited to, ammonium soap, trialkanolamine soap, aminomethyl propanol soap, aminomethyl propanedial soap and tromethamine soap, more preferably triethanolamine soap and aminomethyl propanol soap and the like.

The synthetic surfactants useful in the compositions of this invention are preferably synthetic surfactants selected from anionic, nonionic, amphoteric and zwitterionic surfactants. Preferably, they are present in the compositions of this invention in amounts from about 1 to about 40%, more preferably from about 1 to about 30% and most preferably from about 5 to about 30% by weight of the composition.

Amphoteric Synthetic Surfactants

Ampholytic synthetic detergents can be broadly described as derivatives of aliphatic amines which contain a long chain of about 8 to 18 carbon atoms and an anionic water-solubilizing group, e.g., carboxy, sulfo or sulfato. Examples of compounds falling within this definition are sodium 3-dodecylaminopropionate, sodium-3-dodecylamino propane sulfonate, and dodecyl dimethylammonium hexanoate. Other examples of ampholytic and amphoteric surfactants are found in U.S. Pat. No. 3,318,817, issued to Cunningham 15 on May 9, 1967, and hereby incorporated herein by reference.

The specific preferred examples of amphoteric surfactants are those having the formula:

Zwitterionic Synthetic Surfactants

Zwitterionic surface active agents are broadly described as internally neutralized derivatives of aliphatic quaternary ammonium, phosphonium and tertiary sulfonium compounds, in which the aliphatic radical can be straight chain or branched, and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and one contains an anionic water-solubilizing group, e.g., carboxy, sulfo, sulfato, phosphato, or phosphono. Some of these zwitterionic surfactants are described in the following U.S. Pat. Nos. 2,129,264; 2,178,353; 2,774,786; 2,813,898; and 2,828,332. The specific preferred examples of zwitterionic surfactants are those having the formula:

The water-soluble betaine surfactants are another example of a zwitterionic surfactant useful herein. These materials have the general formula:

Examples of suitable betaine compounds of this type include dodecyldimethylammonium acetate, tetradecyldimethylammonium acetate, hexadecyldimethylammonium acetate, alkyldimethylammonium acetate wherein the alkyl group averages about 12 to 18 carbon atoms in length, dodecyldimethylammonium butanoate, tetradecyldimethylammonium butanoate, hexadecyldimethylammonium butanoate, dodecyldimethylammonium hexanoate, hexadecyldimethylammonium hexanoate, tetradecyldimethylammonium pentanoate and tetradecyldipropyl ammonium pentanoate. Especially preferred betaine surfactants include dodecyldimethylammonium acetate, dodecyldimethylammonium hexanoate, hexadecyldimethylammonium acetate, and hexadecyldimethylammonium hexanoate.

Polymeric Material

As used herein the term “low molecular weight” polymer refers to a polymer having a number average molecular weight (M_(n)) of about 100,000 or less as measured by gel permeation chromatography (GPC) calibrated with a poly(methyl methacrylate) (PMMA) standard. In certain preferred embodiments, low-molecular weight polymers are those having molecular weight ranges of from about 5,000 to about 80,000 M_(n), more preferably from about 10,000 to about 50,000 M_(n), and more preferably between about 15,000 and 40,000 M_(n).

The polymeric material useful in the composition of this invention is preferably a polymeric material suitable for associating anionic and/or amphoteric surfactant thereto and is preferably a non-crosslinked, linear acrylic copolymer that mitigates the impaired dermal barrier damage typically associated with surfactant systems without substantially increasing viscosity build. The non-crosslinked, linear polymers are preferably of low molecular weight having a number average molecular weight of 100,000 or less as measured by gel permeation chromatography (GPC) calibrated with a poly(methyl methacrylate) (PMMA) standard (as used herein, unless otherwise specified, all number average molecular weights (M_(n)) refer to molecular weight measured in such manner). Thus, the polymeric material functions as a copolymeric mitigant. The copolymeric mitigant is polymerized from at least two monomeric components. The first monomeric component is selected from one or more α,β-ethylenically unsaturated monomers containing at least one carboxylic acid group. This acid group can be derived from monoacids or diacids, anhydrides of dicarboxylic acids, monoesters of diacids, and salts thereof. The second monomeric component is hydrophobically modified (relative to the first monomeric component) and is selected from one or more α,β-ethylenically unsaturated non-acid monomers containing a C₁ to C₉ alkyl group, including linear and branched C₁ to C₉ alkyl esters of (meth)acrylic acid, vinyl esters of linear and branched C₁ to C₁₀ carboxylic acids, and mixtures thereof. In one aspect of the invention the second monomeric component is represented by the formula:

CH₂═CRX

wherein R is hydrogen or methyl; X is —C(O)OR¹ or —OC(O)R²; R¹ is linear or branched C₁ to C₉ alkyl; and R² is hydrogen or linear or branched C₁ to C₉ alkyl. In another aspect of the invention R¹ and R² is linear or branched C₁ to C₈ alkyl and in a further aspect R¹ and R² are linear or branched C₂ to C₅ alkyl.

Exemplary first monomeric components include (meth)acrylic acid, itaconic acid, citraconic acid, maleic acid, fumaric acid, crotonic acid, aconitic acid, and mixtures thereof. Exemplary second monomeric components include ethyl(meth)acrylate, butyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, vinyl formate, vinyl acetate, 1-methylvinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl pivalate, vinyl neodecanoate, and mixtures thereof. As used herein, the term “(meth)acrylic” acid and “(meth)acrylate” are meant to include the corresponding methyl derivatives of acrylic acid and the corresponding alkyl acrylate. For example, “(meth)acrylic” acid refers to acrylic acid and/or methacrylic acid and “(meth)acrylate” refers to alkyl acrylate and/or alkyl methacrylate.

More preferably, said first monomeric component is selected from the group consisting of (meth)acrylic acid and said second monomeric component is selected from the group consisting of at least one C₁ to C₉ alkyl(meth)acrylate.

The non-crosslinked, linear acrylic copolymer mitigants of the invention can be synthesized via free radical polymerization techniques known in the art. In one aspect of the invention, the amount of the first monomeric component to the second monomeric component utilized ranges from about 20:80% to about 50:50% by weight, based on the total weight of all of the monomers in the polymerization medium. In another aspect the weight ratio of the first monomeric component to the second monomeric component is about 35:65% by weight, and in a further aspect the weight ratio of first monomeric component to second monomeric component is about 25:75% by weight, all based on the total weight of all monomers in the polymerization medium.

In another aspect emulsion polymerization techniques can be used to synthesize the non-crosslinked, linear acrylic copolymer mitigants that may be useful in the invention. In a typical emulsion polymerization, a mixture of the disclosed monomers is added with mixing agitation to a solution of emulsifying surfactant, such as, for example, an anionic surfactant (e.g., fatty alcohol sulfates or alkyl sulfonates), in a suitable amount of water, in a suitable reactor, to prepare a monomer emulsion. The emulsion is deoxygenated by any convenient method, such as by sparging with nitrogen, and then a polymerization reaction is initiated by adding a polymerization catalyst (initiator) such as sodium persulfate, or any other suitable addition polymerization catalyst, as is well known in the emulsion polymerization art. The polymerization medium is agitated until the polymerization is complete, typically for a time in the range of about 4 to about 16 hours. The monomer emulsion can be heated to a temperature in the range of about 70 to about 95° C. prior to addition of the initiator, if desired. Unreacted monomer can be eliminated by addition of more catalyst, as is well known in the emulsion polymerization art. The resulting polymer emulsion product can then be discharged from the reactor and packaged for storage or use. Optionally, the pH or other physical and chemical characteristics of the emulsion can be adjusted prior to discharge from the reactor. Typically, the product emulsion has a total solids content in the range of about 10 to about 50% by weight. Typically, the total polymer content (polymer solids) of the product emulsion is in the range of about 15 to about 45% by weight, generally not more than about 35% by weight.

In one aspect, the number average molecular weight (M_(n)) of the linear copolymeric mitigants that may be useful in the invention as measured by gel permeation chromatography (GPC) calibrated with a poly(methyl methacrylate) (PMMA) standard is 100,000 or less. In another aspect of the invention, the molecular weight ranges between about 5,000 and about 80,000 M_(n), in a further aspect between about 10,000 and 50,000 M_(n), and in a still further aspect between about 15,000 and 40,000 M_(n).

In one aspect of the invention, the linear copolymeric mitigants have a viscosity of 500 mPa·s or less (Brookfield RVT, 20 rpm, spindle no. 1) at a 5% by weight polymer solids concentration in deionized water and neutralized to pH 7 with an 18% by weight NaOH solution. The viscosity can range from about 1 to about 500 mPa·s in another aspect, from about 10 to about 250 mPa·s in a further aspect, and from about 15 to about 150 mPa·s in a still further aspect.

Preferably, the low molecular weight, non-crosslinked linear acrylic copolymer is potassium acrylates copolymer.

Any of a variety of non-ethoxylated anionic surfactants may be combined with a polymeric material of this invention to form a cleansing composition according to preferred embodiments of the present invention. Non-ethoxylated anionic surfactants are surfactants that have a negative charge and do not contain any ethoxylated segments, that is to say there are no —(C—C—O)_(v) segments on the surfactants. According to certain embodiments, suitable non-ethoxylated anionic surfactants include those selected from the following classes of surfactants: alkyl sulfates, alkyl sulfonates, alkyl monoglyceride sulfonates, alkylaryl sulfonates, alkyl sulfosuccinates, alkyl sulfosuccinamates, alkyl carboxylates, fatty alkyl sulfoacetates, alkyl phosphates, acylglutamates, sarcosinates, taurates, and mixtures of two or more thereof. Examples of certain preferred anionic surfactants include:

alkyl sulfates of the formula

R′—CH₂OSO₃X′;

alkyl monoglyceride sulfates of the formula

alkyl monoglyceride sulfonates of the formula

alkyl sulfonates of the formula

R′—SO₃X′;

alkylaryl sulfonates of the formula

alkyl sulfosuccinates of the formula:

alkyl phosphates

wherein

-   -   R′ is an alkyl group having from about 7 to about 22, and         preferably from about 7 to about 16 carbon atoms,     -   R′₁ is an alkyl group having from about 1 to about 18, and         preferably from about 8 to about 14 carbon atoms,     -   R′₂ is a substituent of a natural or synthetic I-amino acid,     -   X′ is selected from the group consisting of alkali metal ions,         alkaline earth metal ions, ammonium ions, and ammonium ions         substituted with from about 1 to about 3 substituents, each of         the substituents may be the same or different and are selected         from the group consisting of alkyl groups having from 1 to 4         carbon atoms and hydroxyalkyl groups having from about 2 to         about 4 carbon atoms and         -   w is an integer from 0 to 20;             and mixtures thereof.

According to certain embodiments set forth in patent applications U.S. Ser. Nos. 12/822,329 and 12/976,573, the anionic surfactant of this invention is preferably a non-ethoxylated SO_(x) anionic surfactant conforming to the structure below

where SO₃ ⁻ is the anionic hydrophilic group, M⁺ is a monovalent cation (such as NH₄ ⁺, Na⁺, K⁺, (HOCH₂CH₂)₃N⁺, etc.), and R comprises any of a broad range of hydrophobic groups and optionally, a) functional groups to link the hydrophilic and hydrophobic moieties and/or b) additional hydrophilic groups. Examples include:

Alkyl sulfonates, where R equals C₆-C₂₀ alkyl, (linear or branched, saturated or unsaturated), preferably C₁₀-C₁₈, and most preferably C₁₂-C₁₇. Specific examples include Sodium C₁₃-C₁₇ Alkane Sulfonate (R═C₁₃-C₁₇ alkyl, M⁺=Na⁺) and Sodium C₁₄-C₁₇ Alkyl Sec Sulfonate (R=s-C₁₃-C₁₇ alkyl, M⁺=Na⁺)

Alpha olefin sulfonates, where R equals a mixture of

where R₁═C₄-C₁₆ alkyl or mixtures thereof, preferably C₆-C₁₂, more preferably C₈-C₁₂, and most preferably C₁₀-C₁₂. Specific examples include Sodium C₁₂-₁₄ Olefin Sulfonate (R₁═C₈-C₁₀ alkyl, M⁺=Na⁺) and Sodium C₁₄-₁₆ Olefin Sulfonate (R₁═C₁₀-C₁₂ alkyl, M⁺=Nat).

Alkyl sulfate esters, where R₁═C₆-C₂₀,

R₁—O—

(linear or branched, saturated or unsaturated), preferably C₁₂-C₁₆, more preferably C₁₂-C₁₆, and most preferably C₁₂-C₁₄. Specific examples include Ammonium Lauryl Sulfate (R₁=lauryl, C₁₂H₂₅, M⁺=Na⁺), Sodium Lauryl Sulfate (R₁=lauryl, C₁₂H₂₅, M⁺=Na⁺), and Sodium Cocosulfate (R₁=coco alkyl, M⁺=Na⁺).

As used herein, the term “amphoteric” means: 1) molecules that contain both acidic and basic sites such as, for example, an amino acid containing both amino (basic) and acid (e.g., carboxylic acid, acidic) functional groups; or 2) zwitterionic molecules which possess both positive and negative charges within the same molecule. The charges of the latter may be either dependent on or independent of the pH of the composition. Examples of zwitterionic materials include, but are not limited to, alkyl betaines and amidoalkyl betaines as set forth above and below. The amphoteric surfactants are disclosed herein without a counter ion. One skilled in the art would readily recognize that under the pH conditions of the compositions of this invention, the amphoteric surfactants are either electrically neutral by virtue of having balancing positive and negative charges, or they have counter ions such as alkali metal, alkaline earth, or ammonium counter ions.

Examples of amphoteric surfactants suitable for use in this invention include, but are not limited to, amphocarboxylates such as alkylamphoacetates (mono or di); alkyl betaines; amidoalkyl betaines; alkyl sultaines; amidoalkyl sultaines; amphophosphates; phosphorylated imidazolines such as phosphobetaines and pyrophosphobetaines; carboxyalkyl alkyl polyamines; alkylimino-dipropionates; alkylamphoglycinates (mono or di); alkylamphoproprionates (mono or di),); N-alkyl β-aminoproprionic acids; alkylpolyamino carboxylates; and mixtures thereof.

Examples of suitable amphocarboxylate compounds include those of the formula:

A-CONH(CH₂)_(x)N⁺R₅R₆R₇

-   -   wherein     -   A is an alkyl or alkenyl group having from about 7 to about 21,         e.g. from about 10 to about 16 carbon atoms;     -   x is an integer of from about 2 to about 6;         R₅ is hydrogen or a carboxyalkyl group containing from about 2         to about 3 carbon atoms;     -   R₆ is a hydroxyalkyl group containing from about 2 to about 3         carbon atoms or is a group of the formula:

R₈—O—(CH₂)_(n)CO₂ ⁻

-   -   wherein     -   R₈ is an alkylene group having from about 2 to about 3 carbon         atoms and n is 1 or 2; and     -   R₇ is a carboxyalkyl group containing from about 2 to about 3         carbon atoms;

Examples of suitable alkyl betaines include those compounds of the formula:

B—N⁺R₉R₁₀(CH₂)_(p)CO₂ ⁻

-   -   wherein         -   B is an alkyl or alkenyl group having from about 8 to about             22, e.g., from about 8 to about 16 carbon atoms;         -   R₉ and R₁₀ are each independently an alkyl or hydroxyalkyl             group having from about 1 to about 4 carbon atoms; and         -   p is 1 or 2.

A preferred betaine for use in this invention is lauryl betaine, available commercially from Albright & Wilson, Ltd. of West Midlands, United Kingdom as “Empigen BB/J.”

Examples of suitable amidoalkyl betaines include those compounds of the formula:

D-CO—NH(CH₂)_(q)—N⁺R₁₁R₁₂(CH₂)_(m)CO₂ ⁻

-   -   wherein     -   D is an alkyl or alkenyl group having from about 7 to about 21,         e.g. from about 7 to about 15 carbon atoms;         -   R₁₁ and R₁₂ are each independently an alkyl or         -   Hydroxyalkyl group having from about 1 to about 4 carbon             atoms;         -   q is an integer from about 2 to about 6; and m is 1 or 2.

One amidoalkyl betaine is cocamidopropyl betaine, available commercially from Goldschmidt Chemical Corporation of Hopewell, Va. under the tradename, “Tegobetaine L7.”

Examples of suitable amidoalkyl sultaines include those compounds of the formula

wherein

-   -   E is an alkyl or alkenyl group having from about 7 to about 21,         e.g. from about 7 to about 15 carbon atoms;     -   R₁₄ and R₁₅ are each independently an alkyl, or hydroxyalkyl         group having from about 1 to about 4 carbon atoms;     -   r is an integer from about 2 to about 6; and     -   R₁₃ is an alkylene or hydroxyalkylene group having from about 2         to about 3 carbon atoms;

In one embodiment, the amidoalkyl sultaine is cocamidopropyl hydroxysultaine, available commercially from Rhone-Poulenc Inc. of Cranbury, N.J. under the tradename, “Mirataine CBS.”

Examples of suitable amphophosphate compounds include those of the formula:

-   -   wherein         -   G is an alkyl or alkenyl group having about 7 to about 21,             e.g. from about 7 to about 15 carbon atoms;     -   s is an integer from about 2 to about 6;     -   R₁₆ is hydrogen or a carboxyalkyl group containing from about 2         to about 3 carbon atoms;     -   R₁₇ is a hydroxyalkyl group containing from about 2 to about 3         carbon atoms or a group of the formula:

R₁₉—O—(CH₂)_(t)—CO₂ ⁻

-   -   wherein R₁₉ is an alkylene or hydroxyalkylene group having from         about 2 to about 3 carbon atoms and t is 1 or 2; and         R₁₈ is an alkylene or hydroxyalkylene group having from about 2         to about 3 carbon atoms.

In one embodiment, the amphophosphate compounds are sodium lauroampho PG-acetate phosphate, available commercially from Mona Industries of Paterson, N.J. under the tradename, “Monateric 1023,” and those disclosed in U.S. Pat. No. 4,380,637, which is incorporated herein by reference.

Examples of suitable phosphobetaines include those compounds of the formula:

wherein E, r, R₁, R₂ and R₃, are as defined above. In one embodiment, the phosphobetaine compounds are those disclosed in U.S. Pat. Nos. 4,215,064, 4,617,414, and 4,233,192, which are all incorporated herein by reference.

Examples of suitable pyrophosphobetaines include those compounds of the formula:

wherein E, r, R₁, R₂ and R₃, are as defined above. In one embodiment, the pyrophosphobetaine compounds are those disclosed in U.S. Pat. Nos. 4,382,036, 4,372,869, and 4,617,414, which are all incorporated herein by reference.

Examples of suitable carboxyalkyl alkylpolyamines include those of the formula:

wherein

I is an alkyl or alkenyl group containing from about 8 to about 22, e.g. from about 8 to about 16 carbon atoms;

R₂₂ is a carboxyalkyl group having from about 2 to about 3 carbon atoms;

R₂₁ is an alkylene group having from about 2 to about 3 carbon atoms and

-   -   u is an integer from about 1 to about 4.

Any suitable amounts of polymeric material and surfactants may be used in accord with the compositions and methods of this invention. In certain preferred embodiments, the compositions of this invention may comprise from greater than zero to about 6 weight percent of polymeric material (based on active amount of polymeric material in the total weight of composition). In certain more preferred embodiments, the compositions comprise from about 0.1 to about 4.5 weight percent of polymeric material, more preferably from about 0.1 to about 3.5 weight percent of polymeric material, and even more preferably from about 0.2 to about 2.5 weight percent of polymeric material. In the case of cleansing compositions containing amphoteric blends that are substantially free of anionic surfactants, where the composition does not contain cocobetaine, the polymeric material should be present in an amount between about 0.03 and about 2.1 weight percent of the composition. Where cocobetaine is present as a surfactant, there should be less than about 0.03 weight percent or more than about 1.6 weight percent of polymeric material in the composition.

In certain preferred embodiments, the compositions of this invention comprise from about 0.0015 to about 15 weight percent of surfactants based on total active amount of surfactant(s) in the total weight of composition. In certain more preferred embodiments, the compositions comprise from about 2 to about 12 weight percent of total surfactants. Preferred embodiment formulas have from about 2 to about 9 weight percent total surfactants. Preferred embodiments have from about 2 to about 7 weight percent total surfactants. In cases in which cocobetaine is present, said cocobetaine should be present in an amount less than about 0.065 weight percent or greater than about 3.5 weight percent in the composition.

When formulating the compositions of the present invention, when the ratio of non-ethoxylated anionic surfactant to amphoteric surfactant is less than 0.5, the pH of the composition should be between 4.8 and about 6. When the ratio of non-ethoxylated anionic surfactant to amphoteric surfactant is greater than 0.5, the pH of the composition can be less than or equal to 6, preferably between 2.5 and 6.

The non-crosslinked, linear acrylic copolymers useful in the compositions of this invention can be synthesized via free radical polymerization techniques known in the art. In one aspect of the invention, the amount of the first monomeric component to the second monomeric component utilized ranges from about 20:80 wt. % to about 50:50 wt. %, based on the total weight of all of the monomers in the polymerization medium. In another aspect the weight ratio of the first monomeric component to the second monomeric component is about 35:65 wt. %, and in a further aspect the weight ratio of first monomeric component to second monomeric component is about 25:75 wt. %, all based on the total weight of all monomers in the polymerization medium.

The cleansing compositions produced, as well as any of the compositions containing polymeric material and a surfactant component having at least one non-ethoxylated anionic surfactant and at least one amphoteric surfactant that are combined in the combining step according to the methods of this invention may further contain any of a variety of other components nonexclusively including additives which enhance the appearance, feel and fragrance of the compositions, such as colorants, fragrances, preservatives, pH adjusting agents and the like.

Any of a variety of nonionic surfactants are suitable for use in the compositions of this invention, keeping in mind that total surfactant load should not exceed about 14 weight percent of the compositions set forth herein. Examples of suitable nonionic surfactants include, but are not limited to, fatty alcohol acid or amide ethoxylates, monoglyceride ethoxylates, sorbitan ester ethoxylates, alkyl polyglucosides, polyglyceryl esters, mixtures thereof, and the like. Certain preferred nonionic surfactants include alkyl polyglucosides, such as but not limited to coco-glucoside and decyl-glucoside, and polyglyceryl esters, such as but not limited to polyglyceryl-10 laurate and polyglyceryl-10 oleate.

Any of a variety of commercially available secondary conditioners, such as volatile silicones, which impart additional attributes, such as gloss to the hair are suitable for use in this invention. In one embodiment, the volatile silicone conditioning agent has an atmospheric pressure boiling point less than about 220° C. The volatile silicone conditioner may be present in an amount of from about 0 percent to about 3 percent, e.g. from about 0.25 percent to about 2.5 percent or from about 0.5 percent to about 1 percent, based on the overall weight of the composition. Examples of suitable volatile silicones nonexclusively include polydimethylsiloxane, polydimethylcyclosiloxane, hexamethyldisiloxane, cyclomethicone fluids such as polydimethylcyclosiloxane available commercially from Dow Corning Corporation of Midland, Mich. under the tradename, “DC-345” and mixtures thereof, and preferably include cyclomethicone fluids.

Any of a variety of commercially available humectants, which are capable of providing moisturization and conditioning properties to the personal cleansing composition, are suitable for use in this invention. The humectant may be present in an amount of from about 0 percent to about 10 percent, e.g. from about 0.5 percent to about 5 percent or from about 0.5 percent to about 3 percent, based on the overall weight of the composition. Examples of suitable humectants nonexclusively include: 1) water soluble liquid polyols selected from the group comprising glycerine, propylene glycol, hexylene glycol, butylene glycol, dipropylene glycol, and mixtures thereof; 2)polyalkylene glycol of the formula: HO—(R″O)_(b)—H, wherein R″ is an alkylene group having from about 2 to about 3 carbon atoms and b is an integer of from about 2 to about 10; 3) polyethylene glycol ether of methyl glucose of formula CH₃—C₆H₁₀O₅—(OCH₂CH₂)_(c)—OH, wherein c is an integer from about 5 to about 25; 4) urea; and 5) mixtures thereof, with glycerine being the preferred humectant.

Examples of suitable chelating agents include those which are capable of protecting and preserving the compositions of this invention. Preferably, the chelating agent is ethylenediamine tetracetic acid (“EDTA”), and more preferably is tetrasodium EDTA, available commercially from Dow Chemical Company of Midland, Mich. under the tradename, “Versene 100XL” and is present in an amount, based upon the total weight of the composition, from about 0 to about 0.5 percent or from about 0.05 percent to about 0.25 percent.

Suitable preservatives include organic acid preservatives may include benzoic acid and alkali metal and ammonium salts thereof (e.g. sodium benzoate), sorbic acid and alkali metal and ammonium salts thereof (e.g. potassium sorbate), p-Anisic acid and alkali metal and ammonium salts thereof, and salicylic acid and alkali metal and ammonium salts thereof. The pH of the composition may be adjusted to the appropriate acidic value using any cosmetically acceptable organic or inorganic acid, such as citric acid, acetic acid, glycolic acid, lactic acid, malic acid, tartaric acid, or hydrochloric acid.

In one embodiment of the composition, sodium benzoate is present in the composition in an amount, based upon the total weight of the composition, from about 0 to about 0.5 percent. In another embodiment, potassium sorbate is present in the composition in an amount, based upon the total weight of the composition, from about 0 to about 0.6 percent, more preferably from about 0.3 to about 0.5 percent.

The methods of this invention may further comprise any of a variety of steps for mixing or introducing one or more of the optional components described hereinabove with or into a composition comprising a polymeric material before, after, or simultaneously with the combining step described above. While in certain embodiments, the order of mixing is not critical, it is preferable, in other embodiments, to pre-blend certain components, such as the fragrance and the nonionic surfactant before adding such components into a composition comprising a polymeric material and/or an anionic surfactant.

The cleansing methods of this invention may further include any of a variety of additional, optional steps associated conventionally with cleansing hair and skin including, for example, lathering, rinsing steps, and the like.

The foregoing information regarding low molecular weight hydrophobically-modified polymers as well as compositions that may be useful in the methods of this invention are set forth in U.S. Pat. No. 7,803,403, US2006/0257348, and US20070111910, all of which are hereby incorporated herein by reference.

The methods and compositions of this invention illustratively disclosed herein suitably may be practiced in the absence of any component, ingredient, or step which is not specifically disclosed herein. Several examples are set forth below to further illustrate the nature of the invention and the manner of carrying it out. However, the invention should not be considered as being limited to the details thereof.

The topical rinse-off compositions useful in the compositions of this invention may be formulated as solutions. Solutions typically include an aqueous solvent (e.g., from about 50% to about 99.99% or from about 90% to about 99% of a cosmetically acceptable aqueous solvent).

Topical compositions useful in the subject invention may be formulated as a solution comprising an emollient. Such compositions preferably contain from about 2% to about 50% of an emollient(s). As used herein, “emollients” refer to materials used for the prevention or relief of dryness, as well as for the protection of the skin. A wide variety of suitable emollients is known and may be used herein. Sagarin, Cosmetics, Science and Technology, 2nd Edition, Vol. 1, pp. 32-43 (1972) and the International Cosmetic Ingredient Dictionary and Handbook, eds. Wenninger and McEwen, pp. 1656-61, 1626, and 1654-55 (The Cosmetic, Toiletry, and Fragrance Assoc., Washington, D.C., 7^(th) Edition, 1997) (hereinafter “ICI Handbook”) contains numerous examples of suitable materials.

Preferably, the rinse-off compositions of this invention contain from about 1% to about 20% (e.g., from about 5% to about 10%) of an emollient(s) and from about 50% to about 90% (e.g., from about 60% to about 80%) of water.

Topical compositions useful in the subject invention may be formulated as a solution containing an emulsifier. Such compositions preferably contain from about 0.1% to about 1% of an emulsifier. Emulsifiers may be nonionic, anionic or cationic. Suitable emulsifiers are disclosed in, for example, U.S. Pat. No. 3,755,560, U.S. Pat. No. 4,421,769, McCutcheon's Detergents and Emulsifiers, North American Edition, pp. 317-324 (1986), and the ICI Handbook, pp. 1673-1686.

Another type of product that may be formulated from a solution is a creamy cleanser. A creamy cleanser preferably contains from about 5% to about 50% (e.g., from about 10% to about 20%) of an emollient(s) and from about 45% to about 85% (e.g., from about 50% to about 75%) of water.

The topical compositions useful in this invention formulated as emulsions. If the carrier is an emulsion, from about 1% to about 10% (e.g., from about 2% to about 5%) of the carrier comprises an emulsifier(s). Emulsifiers may be nonionic, anionic or cationic. Suitable emulsifiers are disclosed in, for example, U.S. Pat. No. 3,755,560, U.S. Pat. No. 4,421,769, McCutcheon's Detergents and Emulsifiers, North American Edition, pp. 317-324 (1986), and the ICI Handbook, pp. 1673-1686.

The topical rinse-off compositions of this invention may also be formulated as emulsions. Typically such lotions comprise from 0.5% to about 5% of an emulsifier(s). Such creams would typically comprise from about 1% to about 20% (e.g., from about 5% to about 10%) of an emollient(s); from about 20% to about 80% (e.g., from 30% to about 70%) of water; and from about 1% to about 10% (e.g., from about 2% to about 5%) of an emulsifier(s).

Single emulsion skin care preparations, such as lotions and creams, of the oil-in-water type and water-in-oil type are well-known in the cosmetic art and are useful in the subject invention. Multiphase emulsion compositions, such as the water-in-oil-in-water type, as disclosed in U.S. Pat. Nos. 4,254,105 and 4,960,764, are also useful in the subject invention. In general, such single or multiphase emulsions contain water, emollients, and emulsifiers as essential ingredients.

The topical compositions of this invention can also be formulated as a gel (e.g., an aqueous gel using a suitable gelling agent(s)). Suitable gelling agents for aqueous gels include, but are not limited to, natural gums, acrylic acid and acrylate polymers and copolymers, and cellulose derivatives (e.g., hydroxymethyl cellulose and hydroxypropyl cellulose). Suitable gelling agents for oils (such as mineral oil) include, but are not limited to, hydrogenated butylene/ethylene/styrene copolymer and hydrogenated ethylene/propylene/styrene copolymer. Such gels typically comprises between about 0.1% and 5%, by weight, of such gelling agents.

The topical rinse-off compositions of this invention may also be formulated as suspensions. In such a case, the compositions of this invention preferably contain a suspending agent. As used herein, the term “suspending agent” means any material known or otherwise effective in providing suspending, gelling, viscosifying, solidifying and/or thickening properties to the composition or which otherwise provide structure to the final product form. These suspending agents include gelling agents, and polymeric or nonpolymeric or inorganic thickening or viscosifying agents. Such materials will typically be solids under ambient conditions and include organic solids, silicone solids, crystalline or other gellants, inorganic particulates such as clays or silicas, or combinations thereof.

The concentration and type of suspending agent selected for use in the topical leave-on compositions of this invention will vary depending upon the desired product hardness, rheology, and/or other related product characteristics. For most suspending agents suitable for use herein, total concentrations range from about 0.1% to about 40%, more typically from about 0.1% to about 35%, by weight of the composition. Suspending agent concentrations will tend to be lower for liquid embodiments (e.g., pressurized or other liquid sprays, roll-ons, etc) and higher for semi-solid (e.g., soft solids or creams) or solid cleanser embodiments. Preferably, the suspending agents are present in the compositions of this invention in an amount from about 0.1% to about 40%, more preferably, the suspending agents are present in an amount from about 0.1% to about 30.

Non limiting examples of suitable suspending agents include hydrogenated castor oil (e.g., Castor wax MP80, Castor Wax, etc.), fatty alcohols (e.g., stearyl alcohol), solid paraffins, triglycerides and other similar solid suspending esters or other microcrystalline waxes, silicone and modified silicone waxes. Non limiting examples of optional suspending agents suitable for use herein are described in U.S. Pat. No. 5,976,514 (Guskey et al.), U.S. Pat. No. 5,891,424 (Bretzler et al.), which descriptions are incorporated herein by reference.

Other suitable suspending agents include silicone elastomers at concentrations ranging from about 0.1% to about 10%, by weight of the composition. Non-limiting examples of such silicone elastomer materials suitable for use as a suspending agent herein are described in U.S. Pat. No. 5,654,362 (Schulz, Jr. et al.); U.S. Pat. No. 6,060,546 (Powell et al.) and U.S. Pat. No. 5,919,437 (Lee et al.), which descriptions are incorporated herein by reference. These silicone elastomers materials can also be added for their skin feel or other cosmetic benefits alone, or for such benefits in combination with suspending agent benefits.

The topical compositions of this invention can also be formulated into a solid formulation (e.g., a wax-based stick, soap bar composition, powder, or a wipe containing powder).

The topical compositions useful in the subject invention may contain, in addition to the aforementioned components, a wide variety of additional oil-soluble materials and/or water-soluble materials conventionally used in compositions for use on skin, hair, and nails at their art-established levels.

Additional Cosmetically Active Agents

In one embodiment, the topical composition further comprises another cosmetically active agent in addition to the cellulose particles. What is meant by a “cosmetically active agent” is a compound that has a cosmetic or therapeutic effect on the skin, hair, or nails, e.g., lightening agents, darkening agents such as self-tanning agents, anti-acne agents, shine control agents, anti-microbial agents, anti-inflammatory agents, anti-mycotic agents, anti-parasite agents, external analgesics, sunscreens, photoprotectors, antioxidants, keratolytic agents, detergents/surfactants, moisturizers, nutrients, vitamins, energy enhancers, anti-perspiration agents, astringents, deodorants, hair removers, firming agents, anti-callous agents, and agents for hair, nail, and/or skin conditioning.

In one embodiment, the agent is selected from, but not limited to, the group consisting of hydroxy acids, benzoyl peroxide, sulfur resorcinol, ascorbic acid, D-panthenol, hydroquinone, octyl methoxycinnimate, titanium dioxide, octyl salicylate, homosalate, avobenzone, polyphenolics, carotenoids, free radical scavengers, spin traps, retinoids such as retinol and retinyl palmitate, ceramides, polyunsaturated fatty acids, essential fatty acids, enzymes, enzyme inhibitors, minerals, hormones such as estrogens, steroids such as hydrocortisone, 2-dimethylaminoethanol, copper salts such as copper chloride, peptides containing copper such as Cu:Gly-His-Lys, coenzyme Q10, peptides such as those disclosed in U.S. Pat. No. 6,620,419, lipoic acid, amino acids such a proline and tyrosine, vitamins, lactobionic acid, acetyl-coenzyme A, niacin, riboflavin, thiamin, ribose, electron transporters such as NADH and FADH2, and other botanical extracts such as aloe vera, and derivatives and mixtures thereof. The cosmetically active agent will typically be present in the composition of the invention in an amount of from about 0.001% to about 20% by weight of the composition, e.g., about 0.01% to about 10% such as about 0.1% to about 5%.

Examples of vitamins include, but are not limited to, vitamin A, vitamin Bs such as vitamin B3, vitamin B5, and vitamin B12, vitamin C, vitamin K, and vitamin E and derivatives thereof.

Examples of hydroxy acids include, but are not limited, to glycolic acid, lactic acid, malic acid, salicylic acid, citric acid, and tartaric acid and the like.

Examples of antioxidants include, but are not limited to, water-soluble antioxidants such as sulfhydryl compounds and their derivatives (e.g., sodium metabisulfite and N-acetyl-cysteine), lipoic acid and dihydrolipoic acid, resveratrol, lactoferrin, and ascorbic acid and ascorbic acid derivatives (e.g., ascorbyl palmitate and ascorbyl polypeptide). Oil-soluble antioxidants suitable for use in the compositions of this invention include, but are not limited to, butylated hydroxytoluene, retinoids (e.g., retinol and retinyl palmitate), tocopherols (e.g., tocopherol acetate), tocotrienols, and ubiquinone. Natural extracts containing antioxidants suitable for use in the compositions of this invention, include, but not limited to, extracts containing flavonoids and isoflavonoids and their derivatives (e.g., genistein and diadzein), extracts containing resveratrol and the like. Examples of such natural extracts include grape seed, green tea, pine bark, and propolis. Other examples of antioxidants may be found on pages 1612-13 of the ICI Handbook.

Other Materials

Various other materials may also be present in the compositions useful in the subject invention. These include humectants, proteins and polypeptides, preservatives and an alkaline agent. Examples of such agents are disclosed in the ICI Handbook, pp. 1650-1667.

The compositions of this invention may also comprise chelating agents (e.g., EDTA) and preservatives (e.g., parabens). Examples of suitable preservatives and chelating agents are listed in pp. 1626 and 1654-55 of the ICI Handbook. In addition, the topical compositions useful herein can contain conventional cosmetic adjuvants, such as dyes, opacifiers (e.g., titanium dioxide), pigments, and fragrances.

It was found that the hydrophobic cellulose particles useful in the compositions of this invention have excellent water and oil absorption properties. It is believed that the compositions of this invention contain hydrophobic cellulose particles may absorb excess sebum from the skin, thus reducing skin shininess. The compositions of this invention also are believed to protect the skin barrier by forming a hydrophobic layer on the surface of the skin and preventing the penetration of surfactants, emulsifiers or other potentially irritating ingredients. In addition, such a hydrophobic layer formed on the surface of the skin should reduce trans-epithelial water loss and increase hydration of the skin. However, in some instances, it may be desired that the cellulose particles have enhanced or decreased hydrophobic or hydrophilic properties.

Thus, the hydrophobic cellulose particles useful in the compositions of this invention may be treated with additional hydrophobic agents or hydrophilic agents, thus further enhancing hydophobic and/or hydrophilic properties respectively, as desired. Hydrophobic agents may include but not limited to low water soluble organic compounds such as long chain fatty acids or esters such as stearic acid, oleic acid, castor oil, isododecane, silicone, and their derivatives, non-water soluble polymers, e.g. high molecular weight methylcellulose and ethylcellulose, and high molecular water insoluble fluoropolymers etc., polymerized siloxanes or polysiloxanes with the chemical formula [R2SiO]n, where R is an organic group such as methyl, ethyl, or phenyl, such as dimethicone, dimethicone copolyol, dimethicone ester; methicone and their derivatives. Hydrophilic agents such as water soluble polymers, e.g. low molecular weight methyl cellulose or hydroxypropyl methyl cellulose (PMC); sugars, e.g. monosaccharides such as fructose and glucose, disaccharides such as lactose, sucrose, or polysaccharides such as cellulose, amylose, dextran, etc. and low molecular polyvinyl alcohol, and hydrated silica may also be used to enhance the hydrophilic properties of the cellulose particles used in the compositions of this invention.

It also was found that the textures of the compositions formulated with the hydrophobic linear cellulose particles of this invention are “fluffy”, silky and soft and aesthetically pleasing to the touch during and after the application. The term “fluffy” as used herein refers to the bulk density of the hydrophobic linear cellulose particles useful in the compositions of this invention. The bulk density of the hydrophobic linear cellulose particles useful in the compositions of this invention is preferably from about 0.1 to about 2 (g/cm³), more preferably from about 0.15 to about 1.8 g/cm³, and most preferably from about 0.15 to about 1.6 g/cm³. Preferably, the cellulose particles useful in the compositions of this invention are present in the compositions in an amount of from about 1 to about 20% by weight of the compositions, more preferably from about 1 to about 10% by weight of the compositions and most preferably in an amount of from about 1 to about 6% by weight of the compositions.

Methods of Cleansing and Conditioning the Skin or Hair

The methods of this invention also relate to methods of cleansing and conditioning the skin or hair with a personal cleansing product of the present invention. These methods comprise the steps of wetting with water a substantially dry, disposable, single use personal cleansing product comprising a water insoluble substrate, a lathering surfactant, and a conditioning component, and contacting the skin or hair with said wetted product. In further embodiments, the methods and compositions of this invention are also useful for delivering various active ingredients to the skin or hair.

The compositions of this invention may be substantially dry and may be wetted with water prior to use. The product may be wetted by immersion in a container filled with water or by placing it under a stream of water. Lather may be generated from the product by mechanically agitating and/or deforming the product either prior to or during contact of the product with the skin or hair. The resulting lather is useful for cleansing and conditioning the skin or hair. During the cleansing process and subsequent rinsing with water, the conditioning agents and active ingredients are deposited onto the skin or hair. Deposition of conditioning agents and active ingredients are enhanced by the physical contact of the substrate with the skin or hair.

The invention will be further described by reference to the following examples in order to further illustrate the present invention and advantages thereof. These examples are not meant to be limiting but illustrative.

The compounds are indicated, depending on the case, as their CTFA name or their chemical name, and the percentages are given on a weight basis, except where otherwise mentioned.

Example 1 Characterization of Hydrophobic and Hydrophilic Linear Cellulose Fibers

Hydrophobic cotton particles and Hydrophilic Cotton particles listed in Table 1 below were characterized as followed:

Materials:

TABLE 1 Materials Squalene DI Water Hydrophobic Linear Hydrophobic Particles #1 Cotton Particles (available from Goonvean of Cornwall England) Hydrophobic Linear Hydrophobic Particles #2 Cotton Particles (available from IFC of North Tonawanda, NY) Hydrophilic Cotton Hydrophilic Particles #1 Particles (available from Resources of Nature of South Plainfield, NJ)

Example 1A Particle Size Measurement

The particle size of the cellulose materials was determined by Mie/Fraunhofer Laser Scattering method using a Malvern Hydro 2000S Particle Size Analyzer by the following procedure:

-   -   1. Ensured the cell windows and lenses are clean and free from         scratches.     -   2. Flushed (using de-ionized water) and drained the accessory at         least 2 times in order to eliminate any contamination from         previous samples.     -   3. Turned off the pump/stirrer and turned on the ultrasonics for         30 seconds to allow for air bubbles to dissipate.     -   4. Filled the dispersion unit with DI water. Adjusted the         pump/stirrer speed to 2100 rpm, and then turned off the pump for         about 3 seconds to allow the air to dissipate. Then slowly         turned the pump back on to 2100 rpm. Toped up the water in the         dispersion unit to replace the volume of air displaced.     -   5. Added 4 drops of 5% IGEPAL CA 630 (non ionic detergent) in         the tank and allow dispersing before measuring the background.         If this concentration causes bubble formation, cleaned the unit         and repeat the procedure using 2 drops of surfactant. To ensure         the background give a clean value. Follow the 2-150 and 20-20         rule (First two detectors should have light intensity less than         150 units and the detector number 20 should have light intensity         less than 20 units)     -   6. When the system was clean, added diluted sample to be         measured in the dispersion unit in an amount of about 2 mg in 10         grams water.     -   7. When the obscuration caused by the particles in the sample is         2 to 5%, start the measurement. Note D50 and D90 in microns.         (D50 refers to 50% of the particles are less than the value; D90         refers to 50% of the particles are less than the value)     -   8. The experiment was repeated three times and the average of         the three results was recorded as the final value.

The average particle size of various cellulose particles outlined in Table 1 was determined and shown in Table 2.

TABLE 2 Particle Size Particle Size D90 Particle Size D80 D50 (microns) (microns) (microns) Hydrophilic Cotton 170 125 70 Particles Hydrophobic Linear 500 200 55 Cotton Particles (Hydrophobic #1) Hydrophobic Linear 270 125 50 Cotton Particles (Hydrophobic #2)

Example 1B Contact Angle

The contact angles of various cellulose particles outlined in Table 1 were determined as follows:

40 Grams of the cotton particles shown in Table 1 were placed in a particle sample holder; the surface was compressed with a consistent force to create a smooth and compact surface of the particles. 500 μl micro syringe filled with test liquid (water), 0.52 mm needle was used to dispense and deposit 5 μl droplets on the surface. Contact Angles of the droplet on each of the cotton particle samples were measured and calculated with Video-based DataPhysics optical contact angle measuring system OCA 20 with software SCA20 from three replicate tests on each sample, results are shown in Table 3.

TABLE 3 Initial Water Contact Angle Material (degrees) Hydrophobic Linear Cotton 136.2 (5.8)* Particles (#2) Hydrophilic Cotton 39.1 (4)*  Particles Hydrophobic Linear Cotton 122.3 (3.2)* Particles (#1) *represents standard deviation

As shown in Table 3, hydrophobic cotton particles exhibited a larger water contact angle compared to the hydrophilic cotton particles.

Example 1C Infrared Spectra

Infrared spectrum analysis was performed on three cotton particles as follows:

Solvent extraction of the cotton materials using methylene chloride was conducted and followed by IR analysis of the evaporated residues and forth in FIGS. 1 and 2 hereto.

The spectra (shown in FIGS. 1 and 2) showed extract residues from the two hydrophobic linear cotton particles (#2 and #1) along with a dimethicone reference spectrum.

Solvent extractions of the two hydrophobic cotton materials (#2 and #1) showed a significant amount of waxy semi-solid residue, and relatively little from the hydrophilic cotton materials. It is believed that this waxy semi-solid residue coating is responsible for the hydrophobic nature of these two hydrophobic cotton particles.

Infrared analysis of the #2 and #1 hydrophobic cotton residues shows them both to contain silicone (dimethicone or related polymer) along with other components. The #2 residue includes a long chain hydrocarbon wax-like material (as indicated by split peaks around 1375 and 725 cm-1) while the #1 residue includes an ester component (as indicated by IR peaks around 1735 and 1250 cm-1).

The hydrophilic cotton particles (Virgin Cotton Flock) showed negligible extractable residue. The morphology of this material was significantly different from the other two materials indicating a higher degree of processing, reducing much of the cotton fiber into a fine powdery material. The hydrophilic nature of this material is likely due to the inherent absorbent properties of cotton, and the lack of a repellant finish treatment.

Further, Infrared analysis showed that all three cotton materials are typical “cellulosic” materials. Characterization of the three different cotton materials showed the hydrophobic (#2 and #1) being composed of a silicone based hydrophobic treatment. In contrast, the hydrophilic cotton lacks of the silicone based hydrophobic repellant treatment.

Example 2 Specific Surface Area

Inverse Gas Chromatography (IGC) has been reported in various papers as a good method to determine isotherms at finite concentration and ambient temperatures, using organic probe molecules. (Thielmann, F., Burnett, D. J. and Heng, J. Y. Y. (2007) Determination of the surface energy distributions of different processed lactose. Drug Dev. Ind. Pharm. 33, 1240-1253. And see also Yla-Maihaniemi, P. P. et al. (2008) Inverse gas chromatographic method for measuring the dispersive surface energy distribution for particulates. Langmuir, 24, p 9551-9557.

Specific surface area was determined with IGC using octane by measuring the octane adsorption isotherms at 30° C. and 0% RH. The results of these determinations are shown in Table 4. “BET” is a measurement of specific surface area known to those of ordinary skill in the art.

TABLE 4 Specific surface areas of particles (BET/IGC) Sample Surface area (m²/gr.) Hydrophilic Cotton Particles 1.4 Hydrophobic Linear Cotton 1.23 Particles (#1) Hydrophobic Linear Cotton 1.6 Particles (#2)

Example 3 Absorption Capacity and Retention

The absorption capacity of olive oil by the dry cotton particles in Table 1 was measured in standard conditions (i.e. ambient temperature and pressure). The saturated particles were also subjected to centrifugal force to measure their retention power.

When porous media containing liquid is subjected to a force, the liquid is gradually evacuated from large pores then from increasingly small pores as pressure increases. Media containing a high pore volume distribution of smaller pores (or effective pores) can retain more liquid under higher constraint and this retentive power may be a useful feature when the desired role of the media is to retain a liquid (sponge effect).

In order to evaluate the retentive power of the particle, over-saturated oil/particle combinations were subjected to centrifugal force (8000 rpm, 300 seconds) and remaining oil was measured. The results of this measurement are shown in Table 5.

After acceleration, the remaining oil can be expressed as a proportion of the amount of the saturating oil (=mass of oil remaining/mass of oil initially in the blend) or else one can express the amount of oil remaining as a mass fraction of the particle/oil mix (=mass of oil remaining/mass of the particle/oil complex). Both calculations may provide different insights and are expressed in the following table.

TABLE 5 Absorption Capacity and Retention of glyceryl trioleate (olive oil) on Cotton Particles. Absorption capacity of Retention @ 8000 rpm Retention @ olive oil (% (% of 8000 rpm (% of Sample w/w) saturation) blend) Hydrophilic 130 14 16 Cotton Particles Hydrophobic 445 14 38 Linear Cotton Particles (#1) Hydrophobic 322 7 18 Linear Cotton Particles (#2)

The two Hydrophobic Linear Cotton particles (#1 and #2) demonstrated very high absorption of oil in the dry, loosely packed state. Further, the Hydrophobic Linear Cotton Particles (#1) retained a high amount of triglyceride even under applied acceleration.

Example 4 Speed of Oil Absorption

The speed of oil absorption by a material may be determined by Procedures as follows:

A template of a 6×4 cm rectangle was cut from a 0.25 mm thick paper. With a 4×2 cm rectangle window cut in the middle with 1 cm of paper around the edge of the window. A glass microscope slide was weighed and its mass recorded. The template was placed on the slide and the test material dispensed in the window of the template. The material was spread across the window with a metal spatula to create an even rectangular layer with a mass of ˜0.24 g (±0.01 g). The template was carefully removed, edges of the slide cleaned off with a spatula or gloved fingertip as necessary, and the mass of the slide+material recorded. The slide (with oil-absorbing particle layer) was placed flat in an incubator at 32° C. 0.0858 g of the sebum component of interest was dispensed via 0-100 μL pipette (liquids) to the slide at one side of and in contact with the particle layer. (For squalene, 100 μL was used; for triolein, 94.3 μL was used based on suppliers' stated densities). The slide was left undisturbed in the incubator for 15 seconds for follow-up test), with a timer started just as the drop was dispensed. After 15 seconds, the slide was removed from the incubator and any unabsorbed sebum component was carefully wiped from the slide using a Kimwipe. The slide was weighed to determine the amount of the sebum component absorbed by the particles during the absorbance period. The Steps above were repeated for each slide, with each sebum component/particle combination tested at least in triplicate. Ratios were calculated to show the mass of sebum component absorbed per mass of oil-absorbing particle within 15 seconds. The results of this determination are set forth in FIG. 3 hereto.

FIG. 3 demonstrates that cotton particles (#1 cotton particles) absorbs both squalene and triglyceride much faster than hydrophilic cotton particles.

Example 5 Speed of Water Absorption

The speed of water absorption of materials was determined by the procedure set forth as follows:

A gravimetric absorption test (GAT) Method was used to determine the water absorption kinetics of hydrophobic cotton particles vs. hydrophilic cotton particles. The cotton particles sample was loaded into a small cylinder container, and the water was introduced in contact with the cotton particles through a water reservoir on a scale, the change in water weight arising from water transfer or absorption by cotton particles was recorded electronically by a computer over the study duration. The absorption rate was calculated and plotted for different cotton particles samples.

As shown in FIG. 4, hydrophobic cotton particles had a slower water absorption rate than hydrophilic cotton particles.

Example 6 Water Absorption Capacity and Oil Absorption Capacity

The water absorption capacity and oil absorption capacity of materials may be determined by the following procedures set forth below in Examples 6A and 6B.

Each experiment was repeated in triplicate for #1 hydrophobic cotton particles, hydrophilic cotton particles (#1), and #2 hydrophobic Cotton particles.

Example 6A Measurement of Hydrophobicity and Oil Absorption

The scale was tared with the particle samples. Squalene was then added drop by drop via disposable pipette until the sample looked nearly saturated. A metal spatula was used to completely mix in the oil with the particles until saturated. (After mixing, the spatula was wiped clean against the side of the weigh boat to ensure there was no loss of material). “Saturation” as used herein is defined as the mixture being able to hold all the available squalene such that the bottom of the boat appeared dry. This determination was based on the appearance of the mixture and the condition of the weigh boat. The total number of grams of squalene was recorded and the relative Oil Absorption ratio was calculated by dividing the total weight of oil by the total weight of cotton materials. The results of performing this procedure are set forth in FIG. 5 hereto.

Example 6B Measurement of Water Absorption

Following a method similar to that described in example 6A, but substituting water for the oil material, water absorption was measured. The results of this test are set forth in FIG. 6.

Example 7 Cleansing Compositions

TABLE 6 Example Example Example Example Example Example INCI Name 7a 7b 7c 7d 7e 7f Water QS QS QS QS QS QS Glycerin 0.00-15.00  0.00-15.00  0.00-15.00  0.00-15.00  0.00-15.00  0.00-15.00 Acrylates 0.00-12.00 — — — — — Copolymer Acrylates/ — — — — 0.00-1.00 — C10-30 Alkyl Acrylate Crosspolymer Carbomer — — — — — 0.00-1.00 Xanthan Gum — — — 0.00-2.00 — — Sodium 0.00-40.00 — — —  0.00-40.00  0.00-40.00 Laureth Sulfate Decyl —  0.00-14.00 —  0.00-14.00 — — Glucoside Lauryl —  0.00-17.00 — —  0.00-17.00  0.00-17.00 Glucoside Ammonium —  0.00-16.00 — — — — Laureth Sulfate Cocamidopropyl 0.00-17.00 — —  0.00-17.00  0.00-17.00  0.00-17.00 Betaine Cocamide MEA — 0.00-1.00 — — — — Glycereth-7 — 0.00-5.00 — — — — PPG-2 — — — 0.00-2.00 — — Hydroxyethyl Cocamide PEG-16 Soy — — — 0.00-2.00 0.00-2.00 0.00-2.00 Sterol PEG-120 — 0.00-1.60 0.00-2.00 — — — Methyl Glucose Dioleate PEG-80 — — 0.00-3.00 — — — Sorbitan Laurate Cocamidopropyl — — 0.00-2.00 — — — PG dimonium Chloride Phosphate Sodium C14-16 — —  0.00-40.00 — — — Olefin Sulfonate Disodium — — 0.00-5.00 0.00-5.00 — — Lauroamphodi acetate Sodium — — 0.00-5.00 — — — Cocoyl Sarcosinate C12-15 Alkyl — — 0.00-1.00 — — — Lactate Glycol — 0.00-2.00 — — 0.00-2.00 0.00-2.00 Stearate Glycol — — — — 0.00-2.00 0.00-2.00 Distearate Laureth-4 — — — — 0.00-2.00 0.00-2.00 Salicylic — — 0.00-2.00 — — — Acid EDTA 0.00-0.40  0.00-0.40 0.00-0.40 0.00-0.40 0.00-0.40 0.00-0.40 Preservative 0.00-2.00  0.00-2.00 0.00-2.00 0.00-2.00 0.00-2.00 0.00-2.00 Citric Acid QS to QS to QS to QS to QS to QS to adjust adjust adjust adjust adjust adjust pH pH pH pH pH pH Sodium QS to QS to QS to QS to QS to QS to Hydroxide adjust adjust adjust adjust adjust adjust pH pH pH pH pH pH Polyethylene 0.00-2.00  0.00-2.00 0.00-2.00 0.00-2.00 0.00-2.00 0.00-2.00 Fragrance 0.00-1.00  0.00-1.00 0.00-1.00 0.00-1.00 0.00-1.00 0.00-1.00 Cotton 0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00 Particles Hydrophobic Cotton 0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00  0.00-20.00 Particles Hydrophilic

Cleansing compositions of this invention set forth in Table 6 above may be made in accordance with the following procedure:

-   -   1. Add water to a vessel and begin mixing.     -   2. Add Acrylates copolymer or acrylates/C₁₀-₃₀ Alkyl Acrylate         Crosspolymer or Carbomer or Xanthan Gum to the vessel and mix         until completely dispersed.     -   3. Neutralize Carbomer with sodium hydroxide.     -   4. Add Sodium Laureth Sulfate and/or Decyl Glucoside and/or         Lauryl Glucoside and/or Ammonium Laureth Sulfate to the vessel.     -   5. Add Cocamidopropyl betaine (pre-dispersed salicylic acid, if         necessary, in cocoamidopropyl betaine) and/or Cocamide MEA         and/or Glycereth-7 and/or PPG-2 Hydroxyethyl Cocamide and/or         PEG-16 Soy Sterol and/or PEG-120 Methyl Glucose Dioleate to the         vessel.     -   6. Add PEG-80 Sorbitan Laurate and/or Cocamidopropyl PG dimonium         chloridephosphate and/or Sodium C14-16 Olefin Sulfonate and/or         Disodium Lauroamamphodiacetate and/or Sodium cocoyl Sarcosinate         and/or PEG-120 Methyl Glucose Dioleate to the vessel and mix.     -   7. Add Glycol Stearate and/or Glycol Distearate and/or Laureth-4         and/or C12-15 Alkyl Lactate and mix the ingredients.     -   8. Add EDTA and Preservative to the vessel and mix.     -   9. Add polyethlene and fragrance and mix.     -   10. Adjust the pH of the formulation to the desired pH using         sodium hydroxide and/or citric acid.     -   11. Add hydrophobic cotton particles and/or hydrophilic cotton         particles to the mixture.

Example 8 Sebum Absorption Study Using Cleansing Composition

A baseline reading of sebum quantity was taken from selected skin testing sites on the skin surface of nine subjects (Three points—opposite ends and in the middle of the forehead) prior to wetting the skin with water from running faucet. The sebum quantity was measured using a sebumeter. 0.5 cc gel Cleanser (placebo) was applied to skin then the skin massaged for ten seconds. Water was added to the skin and the skin was lathered for additional twenty seconds. Cleanser was rinsed from the skin and any excess residue with water for thirty seconds then blot dried with a Kimwipe.

These steps were repeated with hydrophobic and hydrophilic cotton particles as shown in Table 8 and excess moisture permitted to air dry for about five minutes.

After washing by taking two points spaced out for both the placebo and cotton prototype, sebum count was measured with a sebumeter cartridge consecutively 4 hours and 6 hours after washing, respectively.

For accuracy, each sebum count should be conducted on a fresh skin area (i.e. the same area cannot be measured more than once). Once sebum is measured by the sebumeter cartridge, that particular site will have been disrupted so as to affect accuracy of the measurement of sebum as sebum is produced throughout the day on the skin.

Results of the sebum absorption measurements for Example 9A and 9B are set forth in FIG. 7 hereto (Example 9C was not tested in this example). As can be observed from the graph in FIG. 7, sebum production of skin cleansed with composition containing hydrophobic and hydrophilic cotton particles was slowed as compared with that cleansed with a gel cleanser.

TABLE 8 Example 9B Example 9C Example 9A Hydrophilic Hydrophobic (Gel Cleanser) Cotton Cotton CTFA/INCI Name % w/w % w/w % w/w Water 54.08 48.71 49.26 Sodium Laureth 29.00 29.00 29.00 Sulfate; Water Glycerin 3.00 3.00 3.00 Cocamidopropyl 4.00 4.00 4.00 Betaine Sodium Hydroxide 0.32 0.32 0.32 Disodium EDTA 0.20 0.20 0.20 Phenoxyethanol 1.00 0.00 0.00 (and) Caprylyl Glycol Phenoxyethanol; 0.28 0.00 0.00 Methylparaben; Ethylparaben; Propylparaben Phenoxyethanol 0.00 0.60 0.60 Caprylyl Glycol 0.00 0.00 0.50 (and) Caprylhydroxamic Acid Phenoxyethanol 0.00 0.80 0.00 (and) Caprylyl Glycol Chlorphensin 0.00 0.25 0.00 Citric Acid 0.12 0.12 0.12 Cotton Particles 0.00 5.00 0.00 Cotton Particles 0.00 0.00 5.00 Acrylates 8.00 8.00 8.00 Copolymer 100.00 100.00 100.00 

1-15. (canceled)
 16. A method of removing oil from the skin of a user without irritating the skin of said user, comprising the steps of: (a) wetting a substantially dry skin care composition comprising; (i) hydrophobic, linear cellulose particles having an average length of from about 1 to about 1000 μm, a thickness of from about 1 to about 500 μm, and a particle aspect ratio of from about 1000 to about 2; (ii) at least one cleansing agent selected from the group consisting of a saponified fat and a surfactant; and (iii) a carrier, so as to form a wetted composition; (b) applying said wetted composition to the surface of the skin of the user; (c) forming a hydrophobic layer on the surface of the skin and preventing the penetration of surfactants, emulsifiers, or other irritating components; (d) rinsing said skin care composition off of the surface of the skin.
 17. The method of claim 16, wherein said hydrophobic, linear cellulose particles have an oil absorption capacity and retention of from about 150 to about 500% weight oil/weight particles.
 18. The method of claim 17, wherein said oil absorption capacity and retention of said hydrophobic, linear cellulose particles is from about 300 to about 500% weight oil/weight particles.
 19. The method of claim 16, wherein said particles have an average water contact angle of greater than about 100 degrees.
 20. The method of claim 16, wherein said particles have an average water contact angle of greater than about 120 degrees.
 21. The method of claim 16, wherein said hydrophobic, linear cellulose particles are derived from cotton.
 22. The method of claim 16, wherein said surfactant is selected from the group consisting of anionic, nonionic, and amphoteric surfactants.
 23. The method of claim 16, wherein said composition comprises from about 1 to about 6 percent by weight of said hydrophobic, linear cellulose particles.
 24. The method of claim 16, wherein the aspect ratio of the hydrophobic, linear particle from about 200 to about
 5. 25. The method of claim 16, wherein the length of the linear, hydrophobic particles is from about 10 to about 500 microns and the width of the hydrophobic linear particles is from about 5 to about 25 microns.
 26. A method of removing oil from the skin of a user while increasing hydration of the skin, comprising the steps of: (a) wetting a substantially dry skin care composition comprising; (i) hydrophobic, linear cellulose particles having an average length of from about 1 to about 1000 μm, a thickness of from about 1 to about 500 μm, and a particle aspect ratio of from about 1000 to about 2; (ii) at least one cleansing agent selected from the group consisting of a saponified fat and a surfactant; and (iii) a carrier, so as to form a wetted composition; (b) applying said wetted composition to the surface of the skin of the user; (c) forming a hydrophobic layer on the surface of the skin and preventing trans-epithelial water loss from said skin; (d) rinsing said skin care composition off of the surface of the skin.
 27. The method of claim 26, wherein said hydrophobic, linear cellulose particles have an oil absorption capacity and retention of from about 150 to about 500% weight oil/weight particles.
 28. The method of claim 27, wherein said oil absorption capacity and retention of said hydrophobic, linear cellulose particles is from about 300 to about 500% weight oil/weight particles.
 29. The method of claim 26, wherein said particles have an average water contact angle of greater than about 100 degrees.
 30. The method of claim 26, wherein said particles have an average water contact angle of greater than about 120 degrees.
 31. The method of claim 26, wherein said hydrophobic, linear cellulose particles are derived from cotton.
 32. The method of claim 26, wherein said surfactant is selected from the group consisting of anionic, nonionic, and amphoteric surfactants.
 33. The method of claim 26, wherein said composition comprises from about 1 to about 6 percent by weight of said hydrophobic, linear cellulose particles.
 34. The method of claim 26, wherein the aspect ratio of the hydrophobic, linear particle from about 200 to about
 5. 35. The method of claim 26, wherein the length of the linear, hydrophobic particles is from about 10 to about 500 microns and the width of the hydrophobic linear particles is from about 5 to about 25 microns. 